Reinforced concrete reinvented

Jeroen Smet

Let’s presume

• You all know the benefits of using FRC:• Installation time is 50% of steel mesh• 0% corrosion • 15-40% cheaper solution than steel mesh• 100% Safer

ASTM C 78, JSCE-SF4

Residual Flexural strength

• Concrete = brittle• The bond between the cement and the aggregate => strength

ASTM C 78, JSCE-SF4

Flexural Strength is NOT Increased

Flexural Strain Capacity ISEnhanced

Residual Flexural strength

• FRC => Residual Flexural strength• Fibres take the tension and transfer this tension to un-cracked

areas

Cracks are held together

Residual flexural strength

Test set-up Plain Concrete FRC

Beam test

Brittle Flexural strength

Residual Flexural strength

Residual Flexural Strength

• Re3-value: residual flexural strenght• 3 point bending test• Determined @WTCB

Residual Flexural strength

Design: Slab on grade

Design Service

• Supported floor slab:• Done against CS-TR34-4th edition• In line with the latest Eurocodes and Standards• Limit state format: ULS and SLS• ULS => Meyerhof equations (Partial Safety Factors acc. EC2)

Design service

Comparison of different design methodologies for FRC Slabs on grade - Sunitha K Nayar and Ravindra Gettu

Design service

• ConCribe:• Engineering buro• Experienced with FRC• Floors – Precast designs• PI

• Own Software (sLade) designed by ConCribe• Supported FRC slab• PI • Very fast respons

Design: Slab on grade

Increase energy absorption

Increase energy absorption

• Shotcrete for tunneling requires energy absorption (500,700 &1000 Joule)

• EFNARC plate test ASTM C1550 RDP TEST

Increase energy absorption

Improved impact resistance16mm rebar reinforcement

Improved impact resistanceFibre reinforcement

Improved impact resistanceFibre reinforcement

Improved impact resistanceFibre reinforcement

Durability

• Polypropylene = inert

• Durability of PP fibers in portland cement-based composites: eighteen years of data –D.J. Hannant

• Can be influenced in time by:

• UV radiation

• Oxidation

• Accelerated aging test: EN ISO 13438

• Service life: 25, 50 and 100 years

• 50% residual tensile strength

• S500 lost 32% strength and only 7,1% Modulus (100 years)

Durability

Creep

General:

• Not taken into account in MC 2010• International round robin test (19 labs) supported by RILEM TC

261-CCF• Improving knowledge on creep behaviour of FRC (Steel &

Polymer)• Check different test methodologies

Creep

In Adfil:

• Different fibre generations have been tested• Continiously improved• Phd @ KU Leuven

Creep

Fibre level:

Creep

Focus on segments not subjected to creep:- Flooring & foundations- Shotcrete(1)

- Precast(2)

Structural applications: hybrid reinforcement(3)

(1) Influence of Fibres on the Creep Behaviour of Reinforced Sprayed Concrete presented by Catharine Larive on WTC 2016

(2) PP FRC concrete pipes under sustained loading presented by Emmanuel Attiogbe on BEFIB 2016

(3) Brittle vs. ductile behavior of concrete beams reinforced with steel rebars and fibersGorino, A., Fantilli, A., Chiaia, B., Zampini, D.,

Creep

Creep test on concrete tubes:

- Primary reinforcement

- Longtherm serviceability factor α

- a ≥ 0,90 provides sufficient longtherm post-crack strength

- ASTM C1818 prequalify synthetic fibres for use as primary reinforcement

Applications

• Seawall defence• 4000m³• 4kg/m³• Eleminate corrosion

Applications

• Screed topping 50mm• Not enough covering for steel• 2400m³• 5kg/m³

Applications

• Extruded concrete• >100 Tonnes

Applications

• Housing• Durus S400 adopted as standard

reinforcement in beam and block floors by NHBC

• 4kg/m³

Thank you

Jeroen SmetProduct/Application Managerwww.adfil.be